void StreamChecker::OpenFileAux(CheckerContext &C, const CallExpr *CE) const {
ProgramStateRef state = C.getState();
SValBuilder &svalBuilder = C.getSValBuilder();
const LocationContext *LCtx = C.getPredecessor()->getLocationContext();
DefinedSVal RetVal = svalBuilder.conjureSymbolVal(nullptr, CE, LCtx,
C.blockCount())
.castAs<DefinedSVal>();
state = state->BindExpr(CE, C.getLocationContext(), RetVal);
ConstraintManager &CM = C.getConstraintManager();
// Bifurcate the state into two: one with a valid FILE* pointer, the other
// with a NULL.
ProgramStateRef stateNotNull, stateNull;
std::tie(stateNotNull, stateNull) = CM.assumeDual(state, RetVal);
if (SymbolRef Sym = RetVal.getAsSymbol()) {
// if RetVal is not NULL, set the symbol's state to Opened.
stateNotNull =
stateNotNull->set<StreamMap>(Sym,StreamState::getOpened(CE));
stateNull =
stateNull->set<StreamMap>(Sym, StreamState::getOpenFailed(CE));
C.addTransition(stateNotNull);
C.addTransition(stateNull);
}
}
void IteratorChecker::assignToContainer(CheckerContext &C, const Expr *CE,
const SVal &RetVal,
const MemRegion *Cont) const {
while (const auto *CBOR = Cont->getAs<CXXBaseObjectRegion>()) {
Cont = CBOR->getSuperRegion();
}
auto State = C.getState();
auto &SymMgr = C.getSymbolManager();
auto Sym = SymMgr.conjureSymbol(CE, C.getLocationContext(),
C.getASTContext().LongTy, C.blockCount());
State = setIteratorPosition(State, RetVal,
IteratorPosition::getPosition(Cont, Sym));
C.addTransition(State);
}
bool BuiltinFunctionChecker::evalCall(const CallExpr *CE,
CheckerContext &C) const {
ProgramStateRef state = C.getState();
const FunctionDecl *FD = C.getCalleeDecl(CE);
const LocationContext *LCtx = C.getLocationContext();
if (!FD)
return false;
unsigned id = FD->getBuiltinID();
if (!id)
return false;
switch (id) {
case Builtin::BI__builtin_expect: {
// For __builtin_expect, just return the value of the subexpression.
assert (CE->arg_begin() != CE->arg_end());
SVal X = state->getSVal(*(CE->arg_begin()), LCtx);
C.addTransition(state->BindExpr(CE, LCtx, X));
return true;
}
case Builtin::BI__builtin_alloca: {
// FIXME: Refactor into StoreManager itself?
MemRegionManager& RM = C.getStoreManager().getRegionManager();
const AllocaRegion* R =
RM.getAllocaRegion(CE, C.blockCount(), C.getLocationContext());
// Set the extent of the region in bytes. This enables us to use the
// SVal of the argument directly. If we save the extent in bits, we
// cannot represent values like symbol*8.
DefinedOrUnknownSVal Size =
state->getSVal(*(CE->arg_begin()), LCtx).castAs<DefinedOrUnknownSVal>();
SValBuilder& svalBuilder = C.getSValBuilder();
DefinedOrUnknownSVal Extent = R->getExtent(svalBuilder);
DefinedOrUnknownSVal extentMatchesSizeArg =
svalBuilder.evalEQ(state, Extent, Size);
state = state->assume(extentMatchesSizeArg, true);
assert(state && "The region should not have any previous constraints");
C.addTransition(state->BindExpr(CE, LCtx, loc::MemRegionVal(R)));
return true;
}
}
return false;
}
void IteratorChecker::handleEnd(CheckerContext &C, const Expr *CE,
const SVal &RetVal, const SVal &Cont) const {
const auto *ContReg = Cont.getAsRegion();
if (!ContReg)
return;
while (const auto *CBOR = ContReg->getAs<CXXBaseObjectRegion>()) {
ContReg = CBOR->getSuperRegion();
}
// If the container already has an end symbol then use it. Otherwise first
// create a new one.
auto State = C.getState();
auto EndSym = getContainerEnd(State, ContReg);
if (!EndSym) {
auto &SymMgr = C.getSymbolManager();
EndSym = SymMgr.conjureSymbol(CE, C.getLocationContext(),
C.getASTContext().LongTy, C.blockCount());
State = createContainerEnd(State, ContReg, EndSym);
}
State = setIteratorPosition(State, RetVal,
IteratorPosition::getPosition(ContReg, EndSym));
C.addTransition(State);
}
bool BuiltinFunctionChecker::evalCall(const CallExpr *CE,
CheckerContext &C) const {
ProgramStateRef state = C.getState();
const FunctionDecl *FD = C.getCalleeDecl(CE);
const LocationContext *LCtx = C.getLocationContext();
if (!FD)
return false;
switch (FD->getBuiltinID()) {
default:
return false;
case Builtin::BI__builtin_unpredictable:
case Builtin::BI__builtin_expect:
case Builtin::BI__builtin_assume_aligned:
case Builtin::BI__builtin_addressof: {
// For __builtin_unpredictable, __builtin_expect, and
// __builtin_assume_aligned, just return the value of the subexpression.
// __builtin_addressof is going from a reference to a pointer, but those
// are represented the same way in the analyzer.
assert (CE->arg_begin() != CE->arg_end());
SVal X = state->getSVal(*(CE->arg_begin()), LCtx);
C.addTransition(state->BindExpr(CE, LCtx, X));
return true;
}
case Builtin::BI__builtin_alloca_with_align:
case Builtin::BI__builtin_alloca: {
// FIXME: Refactor into StoreManager itself?
MemRegionManager& RM = C.getStoreManager().getRegionManager();
const AllocaRegion* R =
RM.getAllocaRegion(CE, C.blockCount(), C.getLocationContext());
// Set the extent of the region in bytes. This enables us to use the
// SVal of the argument directly. If we save the extent in bits, we
// cannot represent values like symbol*8.
DefinedOrUnknownSVal Size =
state->getSVal(*(CE->arg_begin()), LCtx).castAs<DefinedOrUnknownSVal>();
SValBuilder& svalBuilder = C.getSValBuilder();
DefinedOrUnknownSVal Extent = R->getExtent(svalBuilder);
DefinedOrUnknownSVal extentMatchesSizeArg =
svalBuilder.evalEQ(state, Extent, Size);
state = state->assume(extentMatchesSizeArg, true);
assert(state && "The region should not have any previous constraints");
C.addTransition(state->BindExpr(CE, LCtx, loc::MemRegionVal(R)));
return true;
}
case Builtin::BI__builtin_object_size: {
// This must be resolvable at compile time, so we defer to the constant
// evaluator for a value.
SVal V = UnknownVal();
llvm::APSInt Result;
if (CE->EvaluateAsInt(Result, C.getASTContext(), Expr::SE_NoSideEffects)) {
// Make sure the result has the correct type.
SValBuilder &SVB = C.getSValBuilder();
BasicValueFactory &BVF = SVB.getBasicValueFactory();
BVF.getAPSIntType(CE->getType()).apply(Result);
V = SVB.makeIntVal(Result);
}
C.addTransition(state->BindExpr(CE, LCtx, V));
return true;
}
}
}
